Police used tear gas and bean bag rounds to quell a protest at the Christmas Island detention centre overnight.

Australian Federal Police (AFP) officers were called to the centre after the protest, involving about 50 detainees, broke out around midnight.

Some detainees climbed onto the roof of the centre and an AFP spokesman said they were brandishing improvised weapons and had lit a number of fires.

The spokesman said police were forced to use tear gas, bean bag rounds and "sound and flash distraction devices" to control the situation.

The AFP said one man had been arrested and investigations were ongoing.

There were no reports of injuries.

The Immigration Department says the protest has now ended and detainees are back in their quarters, however AFP officers remain on site.

Department spokesman Sandi Logan says it is unclear how much damage was caused.

"We are aware that there were several small fires set in wheelie bins and those fires were extinguished immediately by SERCO staff who responded to them," he said.

"At this stage it's too early to say if there's been any damage. That's being assessed as we speak."

Ian Rintoul from the Refugee Action Coalition says the protest is about the length of time taken to process asylum claims.

"I think what we're looking at really is just an expression of the exasperation of people inside the detention centre because they just feel like they've got no alternative but to protest," he said.

"In spite of the protest in March and undertakings that were given then about speeding up the process, nothing has really changed."

Prime Minister Julia Gillard says those involved in the protest could run foul of the new character test for asylum seekers.

"You don't get any changes to the process or to the treatment of your claims by misbehaving," she said.

"Indeed if you misbehave and commit a criminal offence that can count against you because there's a character test for getting a visa."

Home Affairs and Justice Minister Brendan O'Connor says police used appropriate force to quell the protest."The Australian Federal Police is second to none. It's the most professional police force in the world in my view," he said.

"It acts professionally and I'm advised they've acted appropriately and the response was appropriate to the circumstances."

Opposition immigration spokesman Scott Morrison says he is concerned that the Government seems to be treating protests at detention centres as "business as usual".

"The Coalition has long proposed a mandatory enforceable code of conduct in our detention network, where those running the centres have the authority and powers to ensure good public order," he said.

"The Government runs pretty much an 'all carrot and no stick' approach."

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